1. Field of the Invention
The present invention relates to an image sensing apparatus.
2. Description of the Related Art
An image sensing apparatus such as an electronic camera or the like that has a memory card as a recording medium, and records a photographed still image or moving image in this recording medium, and also plays back an image recorded in such a recording medium, is well-known. A view through a lens is displayed on a display unit in such an image sensing apparatus, and the user of the image sensing apparatus can confirm and fix the composition of an image to be sensed while viewing the image displayed on the display unit. Also, photographed images can be played back and displayed on the display unit.
In particular, a function that plays back a photographed image immediately after photography (review function) is highly convenient, and is a beneficial function for the user of the image sensing apparatus. According to the review function, an image photographed immediately before can be confirmed while the image sensing apparatus is still in an image sensing mode. For this reason, because an operation of switching the image sensing device to a playback mode and designating readout processing of image data from a recording medium, image processing, or encoding processing can be omitted, there is an advantage that the user can quickly confirm a photographed image immediately after photography.
Conventionally, although a post-photography review function of a still image is commonplace in such an image sensing device, a review function for reviewing a moving image after its photography has not been adopted. In moving image photography, only a single frame at the end of photography of the moving image is normally displayed, and a review function (hereinafter, RecReview) that allows a user to confirm an important scene on a digest of a moving image immediately after photography of the moving image is desired.
With respect to this, in Japanese Patent Laid-Open No. 2000-350135 (document 1), a frame at the start of recording and a frame at the end of recording of the moving image are stored in a memory. When a review button that designates a review function is pressed by the user, the frame at the start of moving image recording and the frame at the end of recording are read out and displayed on a view finder as a RecReview. By using this technology, the user can confirm from which frame to which frame was photographed in a short time of period immediately after photography of the moving image is complete.
In Japanese Patent Laid-Open No. H06-165009 (document 2), a level of importance is assigned to each button on the camera, and a degree of importance (priority) of frame of moving image is automatically obtained based on the level of importance of a button when the button on the camera is operated during photography of the moving image. Selecting a frame of a moving image to be displayed in accordance with the priority and making possible RecReview that matches the intentions of the user at the time of photographing the moving image is proposed. By using this technology, it is possible to generate a digest image from frames extracted at each scene change in accordance with the operation of a button on the camera. Thus, the user is able to easily confirm important scenes in the photographed moving image after photography of the moving image is complete.
However, because only the frame at the start of photography of a moving image and the frame at the end of photography of the moving image are stored in the memory in the aforementioned document 1, although the scenes at the start and end of photography of the moving image can be confirmed, scenes between the start and end scenes cannot be confirmed. Also, there is the problem that scenes during photography considered to be important by the user cannot be confirmed after the photography of the moving image is complete.
Furthermore, in the camera mentioned in document 2, it is possible to determine the priority of a scene based on the operation of a button, and confirm a scene for which the priority is high immediately after photography of the moving image is complete. However, because it is not possible to consider important scene switches (for example, a rapid change in the luminance of the photographic subject, etc.) for which there is no button operation, there is the possibility that the user may not be able to obtain an intended RecReview image. Also, in the case that operation of the button occurs frequently, the amount of time needed for confirmation can be expected to be long due to the large number of scenes to be confirmed. In this case, the problem remains that the content of the photographed moving image cannot be briefly confirmed in a short amount of time, and the user's intentions cannot be satisfied.